Correction fluids for correcting errors on typewritten and handwritten materials are known in the art. Typically, such correction fluids are opaque material, often white in color but various tinted formulations are available for use on non-white paper. Currently available correction fluids provide an opaque coating over the error and provide a surface for writing or printing the correction. One problem associated with currently available correction fluids is that the color of the correction fluid rarely matches the color of the paper exactly, thereby further drawing attention to the corrected mistake and diminishing the appearance of the finished written product. Further, use of correction fluids changes the texture of the paper and can draw the readers attention to the corrected mistake. Also, if the user begins to write or print over the correction fluid before it is sufficiently dried, the smoothness of the correction fluid surface will be destroyed thereby making the correction sloppy and unprofessional looking.
To eliminate these problems associated with the use of conventional correction fluids, ink eradicators have been developed. An ink eradicator is a liquid material that reacts with the dye of an eradicable ink to change the color of the dye in the eradicable ink from a colored state to a clear or colorless state. In other words, an eradicating fluid can “erase” the inked error.
Typical eradicator fluids are near Newtonian, water-based fluids and are applied by way of a porous tip in fluid communication with a reservoir containing the eradicator fluid. Typically, eradicator fluids are provided in felt tip marker type instruments and the user rubs the felt tip against the incorrect written material until the incorrect written material disappears on the page. Then, after waiting a sufficient amount of time for the eradicator fluid to dry, the user can make the correction with a re-write ink.
Typically, the re-write ink is different than the original eradicable ink because it is resistant to chemical reaction with the dried eradicator fluid. Specifically, the re-write ink does not contain a dye that has the ability to be decolorized by the eradicator or eradicating fluid.
Thus, in current systems utilizing an eradicating fluid as opposed to a correction fluid, three different materials are required: the eradicable ink, the eradicating fluid and the re-write ink. As a result, three different writing instruments may be required: one for the eradicating fluid, one for the eradicable ink and one for the re-write ink. In current systems, it is very easy for the consumer to confuse the eradicable ink, which should be used for the original marking, and the re-write ink, which must be used for the correction because it will not react with the dried eradicating fluid.
To simplify the use of eradicating fluids and eradicable inks, there is a need for an improved eradicable ball-pen ink system which permits the eradicable ball-pen ink to also be used for making the corrections.
In addressing this problem, most ball-pen inks are organic non-polar solvent based. However, most eradicable dyes are not soluble in organic solvents. To make eradicable dyes soluble in non-polar organic solvents, U.S. Pat. No. 6,221,432, commonly assigned with this application, teaches the use of various salts for use as counter ions to provide a hydrophobic property to the eradicable dye thereby rendering it soluble in such non-polar organic solvents. However, this requires additional process steps thereby adding to the cost of such an eradicable ball-pen ink system.
Accordingly, because eradicable ball-pen dyes are typically hydrophilic, a water-based system would be preferable, or a system that does not depend upon the use of non-polar polar organic solvents. Therefore, there is a need for an improved water-based ball-pen ink that is eradicable and can also be used as a re-write ink.